[PATCH] D38057: Try again to fix libcxx CMake so that it doesn't break when no LLVM source tree is available

[Zachary Turner via Phabricator via llvm-commits]

zturner added a comment.

Thanks, I will submit this in a couple of hours when I get into the office.

The llvm side changes are necessary to make `ninja check-libcxx` work (which these bots aren't using anyway)


https://reviews.llvm.org/D38057